Supernova, baryon acoustic oscillations, and CMB surface distance constraints on f(G) higher order gravity models

TL;DR

This paper evaluates higher order gravity models based on f(G) functions against supernova, BAO, and CMB data, finding they fit the data nearly as well as the standard LCDM model, thus remaining viable alternatives.

Contribution

It demonstrates that f(G) gravity models can match observational data as effectively as LCDM, expanding the scope of viable modified gravity theories.

Findings

f(G) models fit supernova, BAO, and CMB data comparably to LCDM

models pass physical and solar system tests

f(G) models remain viable alternatives to dark energy

Abstract

We consider recently proposed higher order gravity models where the action is built from the Einstein-Hilbert action plus a function f(G) of the Gauss-Bonnet invariant. The models were previously shown to pass physical acceptability conditions as well as solar system tests. In this paper, we compare the models to combined data sets of supernovae, baryon acoustic oscillations, and constraints from the CMB surface of last scattering. We find that the models provide fits to the data that are close to those of the LCDM concordance model. The results provide a pool of higher order gravity models that pass these tests and need to be compared to constraints from large scale structure and full CMB analysis.